Polymerization of olefins with a titanium halide-transition metal borohydride catalyst



United States 5 Patent 0 3,189,589 POLYIVERIZATIGN 0F OLEFlNS WETH A TITANI- UM HALDE-TRANSIHON M'ETAL BGRUHY- BRIDE QATALYST Donald R. Witt, Bartlesville, 01th., assignor to Phillips Petroleum Company, a corporation of Delaware No Drawing. Filed July 1, 1960, No. 46,172

13 Claims. (ill. 26093.7)

This invention relates broadly to the polymerization of l-olefins. In another aspect, this invention relates to a novel polymerization catalyst. In still another aspect, this invention relates to a novel and improved polymerization catalyst for l-olefins and method of manufacturing the catalyst.

The polymerization of polymerizable hydrocarbon monomers such as olefins and diolefins by means of various catalyst systems are known in the art. One such catalyst system consists of a transition metal borohydride or hydrocarbon derivative thereof as a polymerization catalyst for the polymerization of olefins and diolefins. In accordance with my present invention, I have now discovered that a catalyst of enhanced utility can be prepared by admixing a transition metal borohydride with a titanium halide.

It is an object of this invention to provide a new and improved polymerization catalyst.

It is another object of this invention to provide a novel method for preparing a catalyst particularly active in polymerizing l-olefins.

Still another object of this invention is to provide an improved process for the polymerization of l-olefins to normally solid polymers.

Still another object of this invention is to provide an improved process for the polymerization of l-olefins to normally liquid polymers.

Other objects, features, and advantages of this invention will be obvious to those skilled in the art from a study of this disclosure and the appended claims.

These objects are broadly accomplished by the method of the present invention by the polymerization of polymerizable oleiinic compounds in the presence of a hydrocarbon solvent and in the presence of a catalyst selected from the group consisting of (A) mixtures of a titanium halide and a transition metal borohydride or these components plus an aluminum trihalide, and (B) isolated precipitates formed in admixtures of titanium halides and transition metal borohydride or these components plus an aluminum trihalide.

In one embodiment of this invention, olefins are polymerized in the presence of a hydrocarbon diluent and a catalyst by contacting said olefin with a catalyst selected from the group consisting of the following:

(1) TiX and M(BH (2) TiX and MUBHQ (3) TiX, and l\/i(l2-H. and AlX' r teger equivalent to the valence of M.

In another embodiment of this invention, olefins are polymerized to liquid polyolefins in the presence of a hydrocarbon diluent by first reacting admixtures of metal halides and metal borohydrides in a hydrocarbon diluent, said admixtures selected from the group consisting of the following:

wherein X is a halide selected from the group consisting of chloride, bromide and iodides; M is at least one transition metal selected from the group consisting of zirconium and hafnium; X is a halide selected from the group consisting of chloride and fluoride; andz is an integer equivalent to the valence of M; separating the resulting solid reaction product, contacting the olefin under polymerization conditions in the presence of a hydrocarbon diluent and said reaction product to produce a liquid polymer and separating said liquid polymer product from said diluent and said catalyst.

In one aspect of this invention, the catalytic components are impregnated on a suitable porous support selected from the group consisting of natural clays and synthetic gels, preferably silica, silica-alumina, alumina,

zirconia, bauxite and thoria prior to use in the polymerization zone.

In another aspect of this invention, the catalytic components are activated by pretreating saidcomponents at elevated temperatures.

In a preferred embodiment of this invention, the catalyst comprises an admixture in hydrocarbon diluent of zirconium and/or hafnium borohydrides and diand tri-valent titanium halides. These metal borohydrides are characterized by the formula M(BH.Q where M is at least one transition metal selected from the group consisting of zirconium and hafnium and x is an integer equal to the valence of M. The second component of the catalyst in this embodiment of the invention comprises a titanium halide characterized by the formula TiX Where X is a halide selected from the group consisting of chloride, bromide, and iodide, preferably chloride and bromide, and y is an integer equal to the valence of titanium not exceeding 3.

Examples of preferred catalyst include TiCl and Zr(BH TiCl and Zr(BH TiCl and Hf(Bl-l TiCl and Hf(BH TiBr and Zr(BH) TiBr and Zr(BH TiBr and Hf(Bl-l TiBr and Hf(BH TiCl and Zr(BH and HHBHQ TiCl and Zr(BH.,) and Hf(BH and the like.

In addition to the aforementioned list of catalysts, it has been discovered that these specific catalysts are assisted in the polymerization of olefins by the addition of a third componentcomprising aluminum trichloride or aluminum trifiuoride. This halide may be hydrated or anhydrous. In particular, the catalytic activity of titanium tetrahalide and the metal borohydride are assisted by the promotion of aluminum trichloride or aluminum triiiuoride when employed in the range of O to 1 mol, preferably 0.2 to 0.5 mol, of aluminum halide per mol of titanium halide plus metal borohydride. Applicant has discovered that the aluminum halide favorably infiuences the rate of polymerization and the yield of polymer and further effects modification of polymer p properties, such as inherent viscosity.

In one aspect of this embodiment of the invention, it

7' theart. V, ,7

catalytic components is preferably eiiected at a temperature within the range of about 150 to 300 F. for a period of 0.1 to 10 hours. The temperature of pretreatment need not be the same as the temperature for polymerization. At the end of the pretreatment period the catalyst components are used as described herein for I the polymerization of the polymerizaible olefins. During the pretreatment the catalytic components may be disper-sed in a hydrocarbon diluent.

In another aspect of this embodiment of this invention, the catalytic components are impregnated or deposited on a suitable oxide porous support selected from the group consisting of natural clays and synthetic gels, preferably silica, silica-alumina, alumina, zirconia, bauxite and thoria. These porous solids are first dried by heating, usually to a temperature in the range of about 500 to 1200 F. for a period of 0.5 to 100 hours in a stream of dry inert gas. Air, nitrogen, hydrogen, helium and the like are suitable inert gases. The dried supports can be conveniently impregnated with the titanium halide and the metal borohydride, by dissolving the desired amount of these compounds in a suitable solvent such as cyclohexane and using the resultant solution to completely saturate the porous solid thereby insuring uniform distribution of the catalytic components; It' is preferred to employ supported catalyst'which contain 0.05 to 20 weight percent,.more preferably 1 to 10 weight percent, of the titanium halide metal borohydride composite. The molar ratio of zirconium and/or hafnium borohydride to titanium halide on the supported catalyst is ordinarily within the range of 0.2 to 3, preferably in the range of 0.3 to 2', and most preferably about 1. In the preparation of the supported catalyst either the titanium halide or the metal borohydride may be first deposited or impregnatedonthe solidsu-pport. How- "not is frequently a liquid although this will depend upon the monomer and the halide used; Thereactionis ordinarily carried' out in ahydrooarbondiluent with the preferred diluents being norm-ally liquid parafiins wd/or naphthenes, although aromatics can be used. Examples of preferred solvents are normal pentane, isooctane and cyclohexane. These catalysts may be either dispersed 'in the hydrocarbon liquid phase asa slurry or dissolved therein depending on the temperature used and the particular catalyst combination used;

The. polymerization of theolefins carrbecarried out at a temperature ranging from 0 F. up to 400 F. with temperatures of 150 F. to 300 F. generally being preferred and a temperature in the range of 225 F. to

operation is not critical but it should be sufdcicnt to maintain a liquid phase in the reactor. Pressures in 'the rangeof .100 to 500 p.s.;i. are normally" used but somewhat higher or lower pressures can be employed. Operation of the polymerization reactor with a vapor" phase in a portion of the reaction system is satisfactory 300 F. being stilljmore preferred. Pressure of'the and even desirable in some cases. In mechanically agitated reactors, operation with a gas cap provides a reservoir of monomer which dissolves in the liquid phase as the polymerization proceeds. This type of'operation is 'well known in the arti The polymer may be separated.

troin the solvent by any convenient method known to f;

In a second embodiment of'this invention, I have discovered that when titanium tetrachloride and a zirconium and/ or hafnium .borohydride are contacted in a hydrocarbon diluent phase solid reaction products are formed Which are isolatab-le and'which are efiective'for promoting polymerization of l-olefins; Further, the solid catalyst prepared according to this embodirnent of the invention has unique properties. 'For'example, an admixture of four or less parts of titanium tetrachloride and one or more parts of zirconium tetrabo'rohydride in a hydrocarbon solvent ordinarily produces a solid polymer when. employed for the polymerization. of pro.- pylene; however, When'using the same combination, the solid reaction product whichis separated from'theslurry produces a liquid polymer of propylene, The liquid polymers of propylene which are produced in accordancewith the process of this invention can be fraction ated to yield dimers, trimers, tetramers, pentainers, and hexamers of high purity. e

To prepare a polymerization catalyst by a method Within the scope of this embodiment, titanium tetrachloride and zirconium and/ or hafnium tetraborohydride are reacted in .a suitable inert medium which is' a solvent for the reaction components." A preferred f'medium'is the liquid hydrocarbon diluent used :in theypolyme'rization react-ion, su ch as the C to C alkanesand cycloalkanes. For example pentane, hexane, Z-methyI bu-tane, heptane, octane, decane, hexadecane, eicosane, cyclohexane, methylcyclohex-ane and the like are employed alone or in admixture with each other'to form a suitable inert medium" for this reaction. .Titanium tetrachloride is readily solublein these hydrocarbons. It is prefer able to add. the zirconium tetraborohydride to the titanium tetrachloride solution ratherlthan vice versa, although either method produces an effective catalyst. An atmosphere of a dried inert gas such as'nit ro-gen is preferably maintained over the system during the. process to prevent contact withmaterials which tend :to deactivate the catalyst, suchas oxygen. 'fj w i The molar ratio of zirconium and/or hafnium borohydrlde'to titanium halide which is r'eacted is. generally between 0.05 to 5.0, preferably 0.1 to 3.0. The reaction proceeds quite rapidly at temperatures between '0 to 250 F. with temperatures in the range of 50 F. to 150 F. being preferred. Any convenient pressure may be used that will maintain'the solvent in the liquid phase.

The solid reaction product which form's is re'coveredby any suitable separation means such as filtration, decantation, centrifugation, or other suitable means. Solution is removed'by washing with additional hydrocarbon diluent and then the reaction product is dried so as to remove free diluent; Satisfactory drying may be achieved in a vacuum oven at pressures below about 1 millimeter fof mercury at temperatures of 50 to 250 F. for periods of 0.5 to hours. The resulting dry productis kept: in an inert atmosphere; Whenreacting titanium tetrachloride and zirconium tetraborohydride it has been observed than an initially formed precipitate is white While a subsequently. formed precipitate is adarh'brown ma terial. The White precipitate and the,'da'rk-brown-precipitate can be mixed and recovered together, as a single reaction. product. Preferably, the total reaction. period is from about 0.1 tolG-Ohours. V i

As willibe' apparent to those skilled in the art, some variation in the technique' of catalyst preparationisQos- 'sible without departing'from the principle of admixing the reactants ina medium which is. a solvent-for both:

solvent so that the solution :containsfrom about 0.002 to 0.2 grarirof reactant per cubic centimeter solution.

In all embodimentsofthe iuventiom'the polymercan be recovered from :the polymerization reaction mixture by any suitable means. .For instance, solid polymer andicate alystmay' -be separated from the reaction mixture by 'filtrae tion, decantation, centrifugation or other conventional means. Liquid products can be distilled to recover the solvent and further distilled to separate the liquid polymer into suitable boiling range fractions. The liquid polymer can also be separated by chromatographic techniques or other well known procedures.

The materials which are polymerized in accordance with this invention can be defined broadly as polymerizable hydrocarbons. Preferably, the polymerizable hydrocarbons are olefins containing a CH =C radical in an alkyl portion of the monomer. The preferred class of polymerizable hydrocarbons used is aliphatic l-olefins having up to and including 8 carbon atoms per molecule. Specifically the normal mcno-1-olefins are preferred. Examples of the preferred olefins include ethylene, propylene, 1- butane, l-hexene, and l-octene. Branched'chain olefins can also be used, such as isobu-tylene. Examples of the diand polyolefinic aliphatic hydrocarbons in which the double bonds are in nonconjugated position and which can be used in accordance with this invention are 1,5- hexadiene, 1,4-pentadiene, and 1,4,7-octatriene. Mixtures of the foregoing polymerizable hydrocarbons can be polymerized to a solid polymer in the presence of the described ca-talyst, as, for example, by copolymerizing ethylene and propylene, ethylene and l butenc, propylene and l-bu-tene, or propylene and a penten This invention is also applicable to the polymerization of a monomeric material comprising conjugated dienes containing from 4 to 8 or more carbon atoms. Examples of conjugated dienes which can be used include 1,3-butadiene, isoprene, 2,3- dimethylbutadiene, Z-rnethoxybutadiene, Z-phenylbutadiene, and the like. it is also within the scope of the invention to polymerize such conjugated dienes either alone or in admixture with each other and/or with one or more other compounds containing an active CHFC group which are copolymerizable therewith. Examples of such compounds are listed hereinabove.

The above enumeration of polymerization reactions promoted by the catalyst of this invention is not intended to be exhaustive but rather illustrates the wide variety of monomers which are polymerized or copolymerized by the method of this invention.

In a specific embodiment of this invention, a catalyst is prepared by admixing a titanium halide, such as titanium trichloride, with a metal borohydride, such as zirconium tetraborohydride, in a hydrocarbon diluent, such as cyclohexane. This catalyst is then introduced into a polymerization reactor with a hydrocarbon diluent, such as cyclohexane, and the reactor maintained at a temperature in the range or" 150 F. to 300 F. at a pressure sufiicient ,to maintain the diluent in a substantially liquid phase.

The olefin, such as a propylene, is then introduced into the reactor and the operating conditions maintained for a period of time, such a 1;-6 hours, sufficient to produce an amount of polymer. Agitation may be provided within the reactor to keep the polymer in suspension. At the end of the polymerization cycle the solvent and excess olefin are separated from the polymer product by any suitable means, such as flashing of the solvent and precipitation of the polymer in a .water bath.

My invention will be further described with reference to the following examples. These examples show the operability of the invention and the advantages thereof and should not be considered limiting in any manner except as taught by the complete specification and claims.

A weighed amount of titanium trichlonde was charged 7 to a steel, 1.4 liter, stirred reactor in a dry, prepurified, m'trogen atmosphere to which was added 3-30 grams of polymerization grade cyclohexane. The metal borohydride, dissolved in cyclohexane, was added by means of a hypodermic syringe. The reactor was then closed and heated to reaction temperature at which time enough propylene (approximately 250' grams) was added to maintain 450 p.s.i. g. at reaction temperature. When the pressure dropped to 440 p.s.i.g. during the run, more propylene was added to maintain 450 psig The propylene was previously dried by passing through Ascarite,* followed by activated alumina. =Runs were of two hours duration.

The footnote reference numerals (1) through (5) are explained at the end of the examples, columns 10 and 11.

EXAMPLE I Usin the procedure described hereinbefore, a run was made with a catalyst comprising 191 grams of titanium trichloride and 0.59 gram of zirconium tetraborohydride. A 230 gram portion of propylene was initially charged to the reactor and 130 grams were added during the polymerization. Test data were:

Total grams solid propylene 167.5 Grams of polymer per gram of total catalyst 99 Grams of polymer per gram of titanium trichloride 152 Isotactic content (1), percent -85 inherent viscosity (2) 2.93 Melt index (3) 0.28 Density (4), gms./cc 0.9033

Flexural modulus (5) 119,000

For comparison, the co-catalyst system of lithium borohydride and titanium trichloride was examined for, propylene polymerization using the aforementioned procedure except for the necessary modification of adding the solid lithium borohydride from a graduated enclosed tube =simi lar to that used for adding titanium trichloride to the reactor. Run data were:

Titanium trichloride grams 0.68 Lithium borohydride do a 0.37 Polymer made Trace The above illustrates the desirability of the borohydride of zirconium, hafnium or combinations thereof.

EYAMPLE H Using the procedure hereinbefore described immediately preceding Example I, hafnium tetraborohydride was examined for propylene polymerization efficacy. The run data were:

Titanium trichloride grams 0.43 Hafnium tetraborohydride do 0.36 Polymer made do 46.3 Grams of polymer per gram of total catalyst 53.5 isotactic content (1) percent 69 For comparison, runs were made using zirconium tetraborohydride, hafnium tetraborohydride and titanium triborohydride alone. Run conditions were similar to those described in Example I with the followin exceptions.

The reactor was charged with 1.03 grams of zirconium etrahorohydride, 300 grams of cyclohexane, and about 250 grams of propylene and heated to 270 F. for 24 hours with a maximum pressure of 580 p.s.i.g. and a minimum pressure of 545 p.s.i.g. Only a trace of polymer was made. Total polymer and catalyst amounted to 1.186 grams.

Using the procedure described immediately above, 1.66 grams of hafnium tetraborohydride was used as the catalyst in a 24-hour run at 240 F. v ith only a trace of Sodium hydroxide asbestos absorbent.

EXAMPLE 111 p Severalruns were made using the reaction conditions hereinbetore described immediately preceding Example I to illustratethe comparative efficacy of different co-cata 8 7. EXAMPLE V M V This example illustrates the usejof an aluminum halide in conjunction with a-titanium halide-metal borohydride co-catalyst system for the polymerization of olefin mon- 'lyst.systems both Pilopylengiand ethylene p a omers. These runs were madein accordance'with the lowing table tabulatesthese runs along with the reaction prbsdurehereinbfor-e .outrfind immediatlv precadeingr conditions, the'reactants, the co-catalyst systems, and the Exam 16 I 7 g 7 j P isotactic content of the polymer. P i e p Tablel Halide Borohydride w. con- Gms. Grns, R N Olefin com (21) 21 525 afiiifiii 3 23? 1111 O. I er Compound Amount, Compound Amount, pound;- V total V gins gms. F. P.s.i.a.r catalyst;- halide 0. 1s Z1(BH-l)4l-- 0.58 Propylene".-- 240 450 19.8 76.3 18.7 V 41.2 1.1 ZICBU-t 4 0. 59 d 240 $8 s2 99 152 r 812% tittaili: 8:39 308 168:5 323 223 0. 4g grg r ngnh 0.2g Propiylenmnu g 22% 5.3 2 5 22.5 137.5 0.4 0... o 6 1.1 Z;(BH:):. 0. 59 Propylene 240 450 167.5 82 99 152 0.64 ZI(BH4)4 0.3' Ethylene 275 300 168.3 185 263 As can 'be seen above, Run 1 compares the efiicacy of p r Table III titanium dichloride with titanium trich'loride in the co- 25 p p catalyst system using zirconium tetraborohydride on prO- Run No 1 2 pylene. It will be seen that although both halides are effective in the polymerization of propylene, the titanium A Catalyst trichloride is the more efiective. g V V g ft g- 8'2; 8-

Run 2 compares the co-catalyst system using zirconium A1F (61%p u r e:-hydrated) b.3 0 tetraborohydride 'eithertitanium trichloride or titanig f33g 2% l 240 um tetrachloride on ethylene. It will be seen from'the Pressure,psi 450 450 above data that both cocatalyst systems are equally effective for the polymerization of ethylene. 0.

Run 3 compares a catalyst comprising titanium trichlo- 35 ride with either hafnium tetraborohydride or zirconium tetraborohydride using propylene as the olefin. It will be Isotactie, percent (1) seen thathatnium oizirconium tetraborohydride are approximately equal in polymerization efi'icacy.

Run 4 compares the same co-catalyst system of titanium 40 It 2 5 322 535 222; gg gi g igP 5 323::' trichloride and zirconium tetrabor'ohydrideion two ditfermm V I p y 1 cut 'olefins, namely, propylene and ethylene. I Although non reapnon anda so modlfies w some ,extent h po'ymer both olefins are readily polymerized, it will be seen that F i v VI the catalyst system is somewhat more effective with V V V v ethylene. V This example illustrates the use of the reaction product EXAMPLE 1V as a polymerization catalyst. V r g example illustrates the improved yields that can I prepqmtian of catalystsA-gombin,aytion reactor'filter be obtained by preheating the catalyst components prior was coltsmlrctfl'd Pyrex l i Me w m nd to the polymen'zation of the monomers. a for flushmewlth'mtrvgenjgas.and W m {m Pl The co-catalyst components were charged to a 1.4 .atmospher? h flaski about 1 me? caPa91tY"Was liter stirred reactor along with 300 grams of cyclohexane, charged Wlth -F F Q and 38 9 cyclic? dispersed and heated to a temperature of 260 F. for a hsxane m? contaulmg 070115 mol 'tltamum. tetra time indicated in Table II'below. After the activation chlorgdee er was f tm a cyclehexahe i d, prgpylene was d itt d t th reactor at a t solution of zlrconium tetraborohydride, the solutionficonso as to maintain polymerization pressure at about 450 taming 0.005 mol Zr(BH The reaction was at room p.s.i.a. At the end of the desired polymerization period, temperature of about.70-'80 F. At first, a white re- V P- the reactor was vented and the polymer was recovered. V c1p1tate formed; and the supernatant h uor above the white q I jTable II i i Gms. 'TiCl; ZI'CBHl); Actva- Condi, Polymer- Condipolymer (gms) (gms) tion, I tions, hrs. ization, F. tions, hrs. per ganlis.

' catalyst 0.62' 0.347 a 2nd 2 240-212 1.5 297 0.34 0.17 V 260 3 235-252 .2.0 r .236 r V 0.31 0.30 260' 3 235-255 2.5 a a 35s 7 By comparing these runs with the runs illustrated in 'EXampleI using the same co-catalyst system and similar :reaction conditions, it will be readily seen that pretreating of. the catalyst prior to introduction to the polymerization zone further improves the ethcacy of the-co-catal yst' system. as a catalysefor the polymerization ot olefin monomers.

5 washings were effected in a nitrogen'atmosphere. The,

precipitate turned brown as additional 1 solid. material 'formed. The entire mixture was intermittently stirred at {about 5 minute intervals tor a period of two hours. The

mixture was then aged about 24 hours, The solid phase was removed by filtration and washed with sir; portions (50 'ml. each). of 'dry cyclohexane. The filtration and product was dried at room temperature at a pressure below 1 mm. of mercury. The dry product was a brown, powdery solid. Analysis of a portion of the product gave the following results:

Component: Weight percent Titanium 22.7 Zirconium 9.8 Boron 0.75

From this analysis the computed Zr/Ti mol ratio is 0.23.

The preparation of this catalyst is summarized in Table IV together with details relating to the preparation of other catalysts B, C and I). These products were prepared by substantially the same process.

Except for catalyst D, 50 ml. of cyclohexane was charged to the desk prior to charging the cyclohexane solutions of H01 and Zr(BH4)s. For catalyst D, the volume was 40 ml.

i'Another similar batch was made. The combined batches were designated as catalyst C and employed for polymerization of olefins.

10 This polymerization run is summarized as Run No. 1 of Table V.

Other polymerization runs.0ther polymerization runs made with the catalyst of Example I are summarized in Table V. These runs were made as described immediately preceding Example I except for indicated variations in process conditions. Thus, for some mus n-pentanewas used as diluent in place of cyclohexane. The volume of n-pentane employed was that calculated to be the same as the volume (3 85 ml.) of cyclohexane. Further, for runs wherein n-pentane was used the reactor was not cooled at the end of the reaction period. Rather, the liquid reaction mixture was passed directly to the distillation vessel and the n-pentane was recovered by distillation. The solid product, if any, was washed with solvent and dried.

Referring to Table V, it is seen that all the catalyst produced loquid polymers of propylene. For the conditions employed the amount of solid polymer was generally less than 25 weight percent of the total product. The liquid products comprised a major amount of material representing C C hydrocarbons, i.e., trimers through hexamers of propylene. 7

Catalyst B produced solid polymer from ethylene (Run 5).

As shown by Run 10, liquid products are also produced with higher olefins. However, some solid polymer also resulted from the polymerization of l-bu-tene.

Table V.P0lymerization of olefirzs Product Analysis oi liquid product Per- Run Cata- Cata- Time, Temp, Pressure, cent No. Solvent lyst lyst, Olefin hr. F. p.s.i.g. resig. Liquid, Solid, Below Cr Cir 015 Cis due 1 Cyclohexane A 1. 53 Propylene, 2 240 450 128. 8 4. 0 6 32 38 18 6 0 -d0 B 0. Q9 d0 2 300 450 62. 2 0 65. 8 0 0 0 0 34. 2

B 1. 14 2 270 450 69. 1 O 58. 1 13. 3 21. 6 7. 1 0 B 1.18 do 2 240 450 60. 7 2. 1 17. 8 29. 6 30. 7 21. 9 0 B 0. 60 Ethylene 1. 5 270 300 0 82. 5 C 0. 91 Propylene- 1 270 450 60. 7 0 25. 4 35. 8 24. 1 l3. 1 1. 5 0 C 1. 0 do 1 270 300 57. 5 0 27. 6 29. 4 27. 2 12. 5 3. 3 0 C 0. 98 2 210 45 62. 7 18. 6 2. 6 38. 5 31. 8 16. 5 10. 6 0 C 1. 06 2 240 450 80. l 2. 6 1. 5 34. 0 38. 1 16. 0 10. 4 0 C 1. 06 2 300 450 43. 0 1. 7 7. 3 36. 3 27. 9 23. 4 5. 1 0 C 1. 26 2 240 450 90. 2 15.0 D 1. 0 Propylene 1 270 450 I 52. 6 3. 5 15. 2 33. 1 23. 2 14. 9 13.6 G 13 do D 0. 90 do 1 300 e50 33.8 0. 4 7. 2 46.1 32. 6 10. 0 4. 1 0

'was sealed and heated to 240 F. within about a 30- minute period. During the next 10-minute interval, 330

grams of propylene was added and the pressure reached 450 p.s.i.g. Thereafter propylene was added at a rate so as to maintain the reaction pressure at about 4-50 p.s.i.g. for a period of 2 hours. The reactor was then cooled to about F. by circulation of cold Water through the reactor jacket. This cooling was eflfected in about 15 minutes. The reactor was then vented to remove excess propylene together with some cyclohexane which was recovered in a trap surrounded with ice.

The liquid phase remaining in the reactor was covered by decantation and distilled at atmospheric pressure to recover cyclohexane. A portion of the kettle product, which amounted to 128.8 grams, was analyzed and found to contain:

Weight percent Propylene trimer V =32 Propylene tetramer 38 Propylene pentamer 18 Propylene hexamer 6 Lighter than trimers -1 6 (l) The isotactic content of each product was determined by placing 25:0.1 grams of polymer in a weighed extraction thimble and extracting in an ASTM Rubber Extraction Apparatus for 2.5 hours with ml' of boiling normal heptane. The thimble was then removed and dried in a forced air oven at C. for 2 hours after which it Was cooled in a desiccator and weighed. The weight percent of residue, based on original polymer, was calculated and recorded as isotactic content.

(2) Inherent viscosity is determined by the method of -Kemp et 211., industrial Engineering Chemistry 35, 1108 (3) For melt index, the method of ASTM D-123 8-52! is used with live runs being run at 2-minute intervals, averaging the five weights, discarding any values which deviate from the average by more than 5 weight percent, reaveraging and multiplying by 5 to obtain the amount of extrudate in 10 minutes. If the melt index is low, such as less than 1.0, the High Load Melt *Index may be obtained by ASTM Dl238-57T (procedure 5) using a weight of 21,600 grams.

(4) Density as used herein is determined by compression molding a slab of the polymer, cooling said moldring at a temperature reduction rate of 15 to 20 F. per

' minute to room temperature, cutting a pea-sized specimen therefrom, and placing said specimen in a SO-ml. glassstoppered graduate. Carbon tetrachloride and methyl cyclohexane are added to the graduate from burettes in proportion such that the specimen is suspended in the 7 solution. During the addition of the liquids the'graduate ferred to a-small test tube and placed on the platform of V a Westphal balance and the glass bob lowered therein. With the temperature shown :by the thermometer in the bob in therange 73 to'78 F., the balance is adjusted until the pointer is at zero. The value shown on thefscale 'is taken as the specific gravity.

() Determined by the method of ASTM D-790-49T.

While certain examples, structures, composition and process steps have been described'for purposes of illustration, the invention is not limited to these. Variation and modification within the scope of the disclosure and the claims can readily be efiected by those skilled in the What I claim is: V

1. A process for the polymerization of polymerizable l-olefins containing a CH =C= radical in the alkyl portion and having 2 to 8 carbon atoms, inclusive, comprising contacting said l-ole fin under polymerization conditions with a catalyst prepared by' reacting (A) TiX and (B) M(Bl-I at a temperature in the range of 0 to 250' F., wherein X is a halide selected from the group consist ing of chloride, bromide and iodide, M is at least one 12 "zirconium .tetraborohydride to titanium dichlor ide'is'in therangeof02to3.

9. The process for the polymerizationof ethylenecom prising contacting. said ethylene wtih a catalyst in the presence of a liquid hydrocarbon diluent at atemperature ange of 0 to 400 F. and a pressure suifi'cient to liquid phase eendiuens'iaa polymerization zone rnaint and separating the r'e'siiltant product, 'said'catalyst'being prepared by" reacting zirconium tetr'aborohydride and titanium trichloride at a temperature in the range of 0 to 250 F. wherein the'molar ratio of the zirconium tetraborohydridte to titanium trichloride'is in therange of and separating the resultant product, said'catalyst being" prepared byreacting zirconium tetraborohydride and titanium tetrachloride at a temperature in the range of 0. to 250 F. wherein the molar ratip of thezirconium tetraborohydride to titanium tetrachloride is the range *of 0.2 to 3. a

transition metal selected from the group consisting of zirconium and hafnium, y is an integer from 2 to 4, and z is an integer equivalent'to the valence of M, wherein the molar ratio of (B) to (A) is in the range of 0.2 to 3.0..

2. The process of claim 1 wherein said admixing results in a solid reaction product which is separated and employed as th'e catalyst for the polymerization process.

3. The process of claim 2 whereinan aluminum halide selected from the'group consisting of aluminumtrichlo- -ride and aluminum trifiuoride is also admixed with (A).

and (B) in the preparation of the catalyst.

' 4. The processof claim ;1 wherein said catalyst is imconsisting of natural clays and synthetic gels.

5. The process of claim 1 wherein said catalyst is preactivated by preheating at a temperature in the range of 150 to 300 F. for a period of 0.1 to 10 hours prior to contacting said olefin for polymerization.

6. The process for the polymerization of propylene comprising contacting said propylene with ,a catalyst in the presence of a liquid hydrocarbon diluent at a temperature in the range of 0 to 400 F. and a pressure sufficient pregnat'edion a .porous support selected from the group to maintain liquid phase conditions in a polymerization a "zone and separating the resultant product, said catalyst being prepared by reacting zirconium tetraborohydnde and titanium trichloride at a temperature in the range of '0 to 250 F. wherein thernolar ratioof the hafnium tetraborohydride to titanium trichloride is in the range of.0.2to3.

8. The process for the polymerization of propylene comprising'contacting saidpropylene with a catalyst in F. and a pressure sut- 11. A process for the polymerizationof ethylene to a liquid polymer which comprises reacting titanium tetrachloride and. zirconium tetraborohydride in the presence of'a liquid hydrocarbon diluent at a temperature in the range of 0 to 250 F. wherein the molar ratio of zirconium tetraborohydride to titanium tetrachloride is inthe range of 0.0510 5.0 at a pressure 'sufficient to maintain the hydrocarbon diluent in a liquid phase for 0.1 to hours, separating the resulting solid reaction product, contacting said ethylene in the presence of a hydrocarbon diluent and saidreaction product in a polymerization zone at a 1 molar ratio of zirconium tetraborohydride to titanium i tetrachloride is in the rangerof 0.25 to 3 and'the'molar ratio of aluminum trifluoride to'the'zirconium tetraboro-' hydride and titanium tetrachloride is in the range of 0 to L'maintaining said polymerization zone at a tempe'rature in the range of 0 to 400 F. at a pressure sufficient to maintain a liquid phase in said zone and separating the resultant sohd product.

13. A process for 'the'polymerization of propylene to.

a liquid polymer which comprises-reacting titanium tetrachloride and zirconium tetraborohydride in the presence,

of a liquid hydrocarbon diluent at a temperature inthe range of 0 to 250 F., 'wherein the molar" ratio of zirconium tetraborohydride totitanium tetrachloride is in the'range of 0.05 to 5.0 at .a pressure sufiicient to main- "tain the hydrocarbon diluent in a' liquid phase for 0.1 to

the presence of a liquid hydrocarbon diluentfat a tem perature in the range of 0 to. 400 F. and a pressuresuf:

ficient to maintain liquid phase conditionsin a polymerization zone and separating the resultant product, said cata- 7 lyst being prepared by reacting zirconium tetraborohyj dride and titanium dichloride'at a temperature in the.

'range of. 0' to250 F. wherein the molar ratio of the i 100 hours, separating the resulting solid reaction product,

- contacting said propylene in the presence of a'hydr o carbon diluent and'saidreaction product in apolym erization zone at a temperature' in the range of'O to 400 F. and a pressure sufiicient to maintain the diluent separating said liquid" polymerproduct." V

Reierenccsflitedhy the Exann fn er}; 1 I UNrTaD srnTEs PATENTS 2 2,728,758] 12 /55 Field at t. zap-494.9.

: (*{Bthcr references on following page) 5 V V in the liquid phase to produce a liquidpoly'mer' and.

1 13 UNITED STATES PATENTS 6/58 Field et a1. 26093.7 121/59 Stuart 26O-93.7

FOREIGN PATENTS 6/ 57' Great Britain. 9/5 8 Great Britain. 9/59 Great Britain.

1 4 OTHER REFERENCES M. LIEBMAN, Examiner. 

1. A PROCESS FOR THE POLYMERIZATION OF POLYMERIZABLE 1-OLEFINS CONTAINING A CH2=C= RADICAL IN THE ALKYL PORTION AND HAVING 2 TO 8 CARBON ATOMS, INCLUSIVE, COMPRISING CONTACTING SAID 1-OLEFIN UNDER POLYMERIZATION CONDITIONS WITH A CATALYST PREPARED BY REACTING (A) TIX, AND (B) M(BH4)Z AT A TEMPERATURE IN THE RANGE OF 0 TO 250*F., WHEREIN X IS A HALIDE SELECTED FROM THE GROUP CONSISTING OF CHLORIDE, BROMIDE AND IODIDE, M IS AT LEAST ONE TRANSITION METAL SELECTED FROM THE GROUP CONSISTING OF ZIRCONIUM AND HAFNIUM, Y IS AN INTEGER FRO 2 TO 4, AND Z IS AN INTEGER EQUIVALENT TO THE VALENCE OF M, WHEREIN THE MOLAR RATIO OF (B) TO (A) IS IN THE RANGE OF 0.2 TO 3.0. 